Downing Street was evacuated this morning but an emergency meeting between Tony Blair and senior ministers at Number 10 continued.

About 50 journalists were ordered to leave their positions on the pavements opposite Number 10 by police after a 'suspect package' was discovered.

They were told simply for their own safety to move from Downing Street across Whitehall to stand outside the Ministry of Defence.

Bomb Squad officers were called in at 8.34am, then at 8.39am a police Range Rover swept across Whitehall from the MoD to take up a position outside number 10.

The all clear was given at 8.52am, but all government buildings are on red alert and Blair wants to reassure the British public that everything is being done to secure the UK against a possible terrorist attack.